SECTION TWO 



ALDEHYDE FUCHSIN 



(after G. Gomori, 1950) 



For elastic tissue, mast cells, beta cells of the pancreatic 



islets, etc. 



Solutions required: 



A. Alcohol 70% 

 Iodine crystals 



B. Sodium thiosulphate 

 Alcohol 96% 

 Distilled water 



C. Basic fuchsin 

 Alcohol 70% 

 Hydrochloric acid, cone. 

 Paraldehyde . . 



100 ml. 

 0-5 gm. 



075 gm. 

 10 ml. 

 90 ml. 



0-5 gm. 

 100 ml. 

 I ml. 

 I ml. 



Dissolve the basic fuchsin in the alcohol; to the cold solution add 

 the acid and the paraldehyde ; shake well ; then leave to stand for about 

 twenty-four hours until the colour of the solution has changed to violet 

 (almost indistinguishable in appearance from gentian violet). As soon 

 as this change has taken place the stain is ready for use. 



Note: The solution will keep for about four weeks at room temperature, 

 but as the stain ages during the four weeks, longer staining times are 

 necessary. 



Technique: 



1. Tissues may be fixed in almost any fixative, but those con- 

 taming dichromate are not recommended as they adversely effect 

 the clearness of the final picture. 



2. Embed in paraffin wax for preference: if celloidin is used, 

 the celloidin must be removed completely from the sections before 

 staining as it is impervious to the stain. 



3. Fix sections to slides and remove paraffin wax in the usual 

 way. 



4. Wash with absolute alcohol followed by 90% alcohol. 



5. Immerse in solution A in a stoppered jar for ten minutes to 

 one hour. 



Note: This treatment with iodine is recommended for all 

 tissues, whether they have been fixed in mercurial fixatives or not, 

 as it often shortens the staining time necessary and makes the 

 shade deeper. 



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